Snapdrop.net let’s you send files between computers with no logins or accounts. It’s easy and straight forward.
Unlike services like Dropbox or Google Drive, Snapdrop doesn’t appear to store your files anywhere. It’s sent once. it’s no longer available for download. So it probably isn’t a great way to collect photos from clients. Rather it’s a great way to send a file from one computer to another without a lot of setup or complication. It’s device agnostic which means to you can use it to send a file from an iPhone to an Android Phone, or from a tablet to a PC.
If you’re interested in the technical aspects, check out their github.